Method and apparatus for cooling syngas within a gasifier system

1. A method of assembling a synthesis gas (syngas) cooler for a gasification system, said method comprising:

positioning a dip tube within a shell of the syngas cooler, wherein the dip tube includes an upstream end and a downstream end, the dip tube is configured to at least one of:

at least partially quench at least a portion of the syngas flowing through the shell; and

at least partially channel at least a portion of the syngas through the dip tube;

coupling an isolation tube to the dip tube such that the isolation tube is substantially concentrically aligned with, and radially outward of, the dip tube, wherein the isolation tube includes an upstream end and a downstream end, the dip tube downstream end is positioned upstream from the isolation tube downstream end, and wherein the isolation tube is coupled in flow communication with a purge gas source and is configured to at least partially form a dynamic pressure seal;

coupling at least one of the isolation tube and the dip tube in fluid communication with a fluid retention chamber; and

at least partially filling the fluid retention chamber with fluid, thereby further forming the dynamic pressure seal.

2. A method in accordance with claim 1 further comprising:

coupling at least one syngas outlet to the shell, wherein the outlet is configured to channel a portion of syngas from the isolation tube; and

coupling at least one spray nozzle within the at least one syngas outlet.

3. A method in accordance with claim 1 further comprising defining at least one purge vent within the isolation tube.

4. A method in accordance with claim 1 further comprising defining a plurality of circumferential openings within at least a portion of the isolation tube.

5. A synthesis gas (syngas) cooler for use within a gasification system, said syngas cooler comprising:

a shell;

a dip tube positioned within said shell, said dip tube comprising an upstream end and a downstream end, said dip tube is configured to at least one of:

at least partially quench at least a portion of a syngas flowing through said shell; and

at least partially channel at least a portion of the syngas through said dip tube;

an isolation tube comprising an upstream end and a downstream end, said isolation tube coupled to said dip tube such that said isolation tube is substantially concentrically aligned with, and radially outward of, said dip tube, wherein said dip tube downstream end is positioned upstream from said isolation tube downstream end, and wherein said isolation tube is coupled in flow communication with a purge gas source and is configured to at least partially form a dynamic pressure seal; and

a fluid retention chamber coupled in flow communication with at least one of said isolation tube and said dip tube, wherein said fluid retention chamber is at least partially filled with fluid and is configured to further form said dynamic pressure seal.

6. A syngas cooler in accordance with claim 5 further comprising:

at least one syngas outlet coupled to said shell, said syngas outlet configured to channel a portion of the syngas from said isolation tube; and

at least one spray nozzle coupled to said at least one syngas outlet.

7. A syngas cooler in accordance with claim 6 wherein said at least one syngas outlet is positioned between said shell and at least one splash plate, wherein said at least one splash plate is coupled to said isolation tube.

8. A syngas cooler in accordance with claim 5 wherein at least one of said dip tube downstream end and said isolation tube downstream end is serrated.

9. A syngas cooler in accordance with claim 5 wherein said isolation tube downstream portion defines a plurality of circumferential openings.

10. A syngas cooler in accordance with claim 5 wherein said downstream end of said dip tube is one of:

at least partially immersed within the fluid within said fluid retention chamber; and

positioned upstream of the fluid within said fluid retention chamber.

11. A syngas cooler in accordance with claim 5 wherein said dip tube is one of a cylindrical and frusto-conical configuration.

12. A syngas cooler in accordance with claim 5 further comprising a syngas chamber defined upstream from said dip tube such that said syngas chamber is configured to channel syngas into said dip tube.

13. A syngas cooler in accordance with claim 5 further comprising at least one baffle tray coupled within said shell.

14. A syngas cooler in accordance with claim 5 further comprising at least one purge vent defined within said isolation tube, wherein said at least one purge vent is one of fixed opening and selectively operable configurations.

15. A syngas cooler in accordance with claim 5 further comprising at least one seal positioned between said syngas outlet and said isolation tube.

16. A syngas cooler in accordance with claim 5 further comprising at least one quenching mechanism.

17. A gasification system comprising:

at least one gasifier configured to produce a synthesis gas (syngas); and

at least one syngas cooler coupled in flow communication with said gasifier, said at least one syngas cooler comprising:

a shell;

a dip tube positioned within said shell, said dip tube comprising an upstream end and a downstream end, said dip tube is configured to at least one of:

at least partially quench at least a portion of the syngas flowing through said shell; and

at least partially channel at least a portion of the syngas through said dip tube;

an isolation tube comprising an upstream end and a downstream end, said isolation tube coupled to said dip tube such that said isolation tube is substantially concentrically aligned with, and radially outward of, said dip tube, wherein said dip tube downstream end is positioned upstream from said isolation tube downstream end, and wherein said isolation tube is coupled in flow communication with a purge gas source and is configured to at least partially form a dynamic pressure seal; and

a fluid retention chamber coupled in flow communication with at least one of said isolation tube and said dip tube, wherein said fluid retention chamber is at least partially filled with fluid and is configured to further form said dynamic pressure seal.

18. A gasification system in accordance with claim 17 further comprising:

at least one syngas outlet coupled to said shell, said syngas outlet is configured to channel a portion of the syngas from said isolation tube; and

at least one spray nozzle coupled to said at least one syngas outlet.